وبلاگ طرفداران محيط زيست اردبيل

2008-09-14T00:36:00.000-07:00

2008-09-13T11:41:00.000-07:00

تصاویری از غرفه اداره کل حفاظت محیط زیست اردبیل در نمایشگاه اردبیل واقع در سالن امام خمینی 86

زیستگاههای یوز پلنگ در ایران

2008-09-12T00:09:00.000-07:00

زيستگاههاي يوز پلنگ در ايران

زيستگاه عمده يوزپلنگ در ايران دشت كوير است كه بخش هايي از استانهاي كرمان، خراسان، سمنان، يزد، تهران و مركزي را در برمي گيرد. اكنون اين ناحيه وسيع استپي و بياباني به آخرين پناهگاه يوز آسيايي مبدل شده است. به طور مشخص و كاملا واضحي طي دو دهه اخير تعداد گزارشهاي رسيده از اين ناحيه وسيع در مورد مشاهده يوز كاهش يافته و تنها گزارشات معدودي از مشاهده جانور در پارك ملي كوير، مناطق توران، نايبندان، دره انجير، مياندشت و خوش ييلاق بدست آمده است. اين درحالي است كه بين سالهاي 46 تا 57 گزارشاتي از تهران (به خصوص پارك ملي كوير)، سمنان (توران، خوش ييلاق و مناطق اطراف)، خراسان (منطقه مياندشت و مناطق اطراف طبس)، يزد (منطقه كالمند و مناطق ديگر اطراف بافق، مهريز، تفت و شهر يزد)، اصفهان (منطقه موته و كلاه قاضي)، فارس (پناهگاه حيات وحش بهرام گور)، كرمان (منطقه خبرو روچون)، مازندران (پارك ملي گلستان)، هرمزگان (اطراف حاجي آباد) و نيز گزارشات غير مكتوبي از سيستان( اطراف هامون صابري) و بلوچستان (بمپور) و حتي نفت شهر در استان كرمانشاه مبني بر مشاهده يوز وجود داشته است.
اين روزها پناهگاه حيات وحش نايبندان طبس، پارك ملي خارتوران سمنان به همراه سه منطقه ديگر يعني پارك ملي كوير و مناطق دره انجير و بافق از معدود مكان هايي اند كه هنوز يوز در آن ها مشاهده مي شود و از جمعيت هاي اندك باقي مانده اين جانور باشكوه پشتيباني مي كنند. (جوكار، هومن ،پايان نامه كارشناسي دانشگاه آزاد واحد تهران شمال، 1378)
١ - پارك ملي كوير استان سمنان، مساحت ۴۰۰،۰۰۰ هكتار، ۴ واحد محيط بانى، برآورد جمعيت يوزپلنگ: ۴-۶ قلاده. پارك ملى كوير در ۵۰ كيلومترى جنوب غربى تهران است. اين منطقه كه زمانى «آفريقاى كوچك» ناميده مىشد يك زيستگاه غنى از نظر تنوع زيستى در کشور است. گونه‌هاى حيوانى منطقه عبارتند از: جبير، آهو، قوچ و ميش وحشى، کل و بز وحشى، كفتار، پلنگ، گرگ، و گونه‌هاى نادر گربه‌سان كوچك ازجمله گربه‌شنى و کاراکال است. . ٢ - پارك ملى، پناهگاه حيات وحش و ذخيره‌گاه زيست‌کره خارتوران استان سمنان، مساحت ۱،۴۰۰،۰۰۰ هكتار، ۵ واحد محيط بانى، برآورد جمعيت يوزپلنگ: ۱۰-۱۴ قلاده. خارتوران يكى از مهمترين و ارزشمندترين مناطق ويژه تحت نظارت سازمان حفاظت از محيط زيست مىباشد و مجموعه‌اى از تقريباً تمامى گونه‌هاى جانداران صحرايى ايران از جمله جبير، آهو، قوچ و ميش وحشى، کل و بز وحشى، كفتار، پلنگ، گرگ، يوزپلنگ را پناه ميدهد و يكى از دو پناهگاه باقيمانده براى گور است. تعداد گورهاى موجود در اين پارك ملى ۲۵۰ الى ۳۰۰ رأس برآورد شده است

٣ - پناهگاه حيات وحش نايبندان طبس شمال شرق استان يزد، ۱،۵۰۰،۰۰۰ هكتار، ۴ واحد محيط بانى، برآورد جمعيت يوزپلنگ: ۱۲-۱۵ قلاده. اين منطقه از جديدترين مناطق تحت کنترل سازمان حفاظت از محيط زيست بوده و در زمره مهمترين زيستگاه‌هاى يوز قرار گرفته است. انواع وحوش کويرى و نيمه‌کويرى، از جمله روباه، شاه‌روباه، جبير، قوچ و ميش وحشى، آهو، خرگوش، كفتار، گربه شنى، کل و بز وحشى، و گرگ در اين منطقه ديده مي شوند.
٤ - منطقه حفاظت شده بافق استان يزد، ۱۵۰،۰۰۰ هكتار، ۲ واحد محيط بانى، برآورد جمعيت يوزپلنگ: ۴-۶ قلاده. بافق در ۱۰۰ كيلومترى شرق يزد است و آب و هوايى بسيار خشك دارد. گونه‌هاى حيوانى اين منطقه آهو، قوچ و ميش وحشى، کل و بز وحشى، كفتار، پلنگ، و گرگ است.
٥ - منطقه شكار ممنوع دره‌انجير استان يزد، ۱۵۰،۰۰۰ هكتار، ۱ واحد محيط بانى، برآورد جمعيت يوزپلنگ: ۳-۵ قلاده. اين منطقه داراى محيطى زيست شكننده و آسيب‌پذير بوده و از پوشش گياهى فقيرى برخوردار است. گونه‌هاى جانورى از قبيل جبير، قوچ و ميش وحشى، کل و بز وحشى در اين منطقه مشاهده مي شود.

تهديدهاى غيرزيستگاهی: شکار مستقيم وحوش در ايران با وفور فزاينده سلاح گرم و استفاده از خودرو براى شكار همبستگى کامل دارد. اكثر شكارچيان غيرقانونى از اهميت يوزپلنگ و طعمه‌هاى آن در نظام بوم‌شناختى آگاه نيستند و شكار غيرقانونى در نظر آنها جرمى ناچيز به حساب مي آيد. علاوه بر شكار غيرقانونى، سالانه حدود يك ميليون مجوز شكار با سهميه ۳۰۰ گلوله به‌ طور رسمى صادر مي شود. بايد به تمامى اين تهديدها بهره‌بردارى تجارى از گونه‌هاى خاص را نيز افزود که به صورت بي رويه ادامه دارد. گونه‌هايى چون آهو، پلنگ، باز، هوبره، کبک، مرغابى و تمساح از جمله گونه‌هاى در خطرند. با توجه به تعداد اندک يوزپلنگ باقى مانده در مناطق ، و به خاطر اينکه نسبت ماده به نر اين گونه هنوز روشن نيست، با شکار هر يک گربه‌سان لطمه سنگينى به نظام ژنتيکى گونه در حال انقراض وارد مىشود. متأسفانه نظارت بر شکار غيرقانونى دشوار است؛ به عنوان مثال، زيستگاه‌هاى يوز غنى از كانيهاى مهم صنعتى و تجارى است كه توسط وزارت صنايع و معادن مورد بهره‌بردارى قرارگرفته مي شود. استخراج معدن به خودي خود تهديدى محسوب نمي شود اما جاده سازىْ مناطق مذكور را براى همگان، از جمله شكارچيان غيرقانونى، قابل دسترس ميكند.

توصيف يوزپلنگ آسيايي
دست و پاهاي بلند، بدنى باريك و كشيده، سينه فراخ و شكم بالاي او شبيه تازي است ولي بر خلاف سگ سانان سر كوچك و گرد، پوزه اي كوتاه و گوش هايي كوچك و گرد دارد. به طور كلي مي توان آن را به" سگي با كله گربه" تشبيه نمود. رنگ پشت زردكمرنگ تا زرد متمايل به قرمز و زير بدن سفيد است. خالهايى گرد، سياه و توپر و موهايى زبر و نسبتا كوتاه دارد. در بالغين خال هاي روي دم تدريجا در نيمه انتهايي به حلقه هايي بدل مي شود كه سياه رنگ اند و آخرين حلقه پهن تر است. سر يوزپلنگ كوچك و گرد است و چشمانش در بالاى كاسه سر قرار دارد. خط سياه شكيلي معروف به خط اشكي از گوشه چشمان يوزپلنگ تا اطراف بينى و دهانش امتداد دارد كه احتمالا چشمان او را از آفتاب مصون مي دارد و در شكار به او كمك مي كند. جانور بالغ ناخن‌هايى كند و نيمه تورفته دارد كه برخلاف ساير گربه سانان جمع نمي شوند.( هرچند بچه ها تا 6 ماهگي قادرند ناخن ها را جمع كنند.)
اندازه: طول سر و بدن يوزپلنگ بالغ بر ۱۱۲ تا ۱۳7 سانتيمتر، طول دم ۶4 تا 86 سانتيمتر و بلندى شانه‌هايش 71 تا 84 سانتيمتر است و وزن حيوان به ۳۴ تا ۵۴ كيلوگرم مىرسد. جنس نر يوز اندكى بزرگتر از جنس ماده است.( اين اندازه ها مربوط به نمونه هاي جمعيت آسيايي است)
خصوصيات: برخوردارى از ستون فقرات انعطاف‌پذير، كبد و قلب بزرگ، سوراخ بينى گشاد، ظرفيت بالاى ريه، بدن عضلانى و باريك، يوزپلنگ را تيزروترين شكارچى جهان ساخته است. آنها قادرند با سرعتي معادل 110 كيلومتر در ساعت بدوند.
زيستگاه: يوزپلنگ در دشت هاي بازو تپه ماهورهاي واقع در مناطق استپي و بياباني نيمه كويرى و زيستگاههاى باز ديگرى كه طعمه در آن وجود داشته باشد ديده مي شود. در ايران تعداد معدود يوزپلنگ آسيايى باقيمانده در مناطق حاشيه اي كوير مركزي يافت مي شوند.
عادت و رفتار : يوزپلنگ از نظم اجتماعى منحصربه‌فردى برخوردار است. در ايران مطالعاتى درباره يوزپلنگ صورت نگرفته است، اما مطالعات انجام شده در آفريقا نشان مي دهد كه يوزپلنگ ماده به استثناي زمان مراقبت از توله ها به تنهايي زندگى مي كند و يوز پلنگ نر در مراقبت از بچه ها نقشي بر عهده ندارد. توله ها به مدت هجده ماه در كنار مادرشان مي مانند و طي اين دوره كه از اهميتى بالا در در زندگى توله ها برخوردار است، چگونگى شکار و گريز از گزند شكارچيان ديگر مانند پلنگ، كفتار و گرگ را مي آموزند.
در ۱۸ ماهگى توله ها از مادر جدا مي شوند. از اين پس ممکن است توله‌ها با هم‌شيران خود حتى تا ۶ ماه به سر برند. در دو سالگى هم‌شيران مادهْ بقيه را ترك مي کنند و نرهاى جوان با هم مي مانند. در واقع نرها به تنهايى يا همراه با برادران خونى خود زندگى مي كنند اما ماده ها به جز زمان بچه داري، تنها زندگي مي كنند. برخى از اين گروهها براى خود حوزه اي تعيين ميكنند تا يوزپلنگ ماده را براى جفت‌گيرى جلب کنند. اين حوزه ها اغلب در جاهايى است كه در آن طعمه و آب كافي وجود داشته باشد. در فصل جفت گيري هر نر براي خود قلمروي را انتخاب مي كند، در اين فصل نزاع هاي خشني ميان نرهاى گروه در دفاع از حدّ و مرز قلمرو‌شان صورت مي گيرد. يوزپلنگ ها معمولاً صبح زود يا غروب به شكار مي روند، پس از انتخاب طعمه كه معمولا حيوانات ضعيف تر مي باشند به صورت غير محسوس به آنها نزديك شده و پس از رسيدن به فاصله حدود ۱۰ تا ۳۰ متر حمله ناگهاني خود را شروع مي كنند، پس از به زمين انداختن طعمه گلوي او را با دندان هايش فشار مي دهد تا خفه شود. تعقيب طعمه معمولا ۲۰ ثانيه و به ندرت بيش از يك دقيقه بطول مى انجامد و در اين زمان بيش از 500 متر شكارش را دنبال نمي كند. قريب به نيمى از تعقيب‌ها موفق‌آميزند. برخي اوقات شكارچيان ديگر نظير گرگ طعمه او را از چنگش بيرون مي آورند. يوزپلنگ مانند پلنگ قادر به پنهان كردن طعمه اش از دسترس ساير گوشتخواران نيست و به همين دليل بعد از خوردن يك وعده غذا در بيشتر اوقات باقيمانده را از دست مي دهد.
توليدمثل: بلوغ جنسى در حدود ۲۰ ماهگى رخ مي دهد. زمان بارداري 95 روز و تعداد توله‌ها 1 تا 6 و معمولا ۴ تا ۵ عدد است. توله ها در هنگام تولد حدود ۳۰۰ گرم وزن و ۳۰ سانتيمتر طول دارند. رنگ آنها خاكسترى تيره است و موهاى بلندي بر پشتشان دارند. اين موها چند فايده دارد، از جمله استتار آنها در ميان بوته زار هاي خشك و پنهان نگاهداشتن آنها از ديدرس شكارچيان ديگر. اين موها همچنين توله يوز را به" رودك كه حيوان مهاجمي است شبيه مي کند، که نوعى جنبه دفاعى دارد. بچه ها به دليل جمع شدن ناخنها تا شش ماهگي قادرند از درخت بالا بروند.
تغذيه: يوزپلنگ در ايران عمدتاً از جبير، آهو، قوچ و ميش، كل و بز و خرگوش وحشي تغذيه مي كند.

biodiversity

2008-09-06T00:40:00.001-07:00

Biodiversity
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It has been suggested that Biodiversity information be merged into this article or section. (Discuss)

Rainforests are among the most biodiverse ecosystems on earth
Biodiversity is the variation of life forms within a given ecosystem, biome or for the entire Earth. Biodiversity is often used as a measure of the health of biological systems.
Biodiversity found on Earth today consists of many millions of distinct biological species, the product of four billion years of evolution.
Contents
1 Evolution and meaning
2 Definitions
3 Measurement
4 Distribution
5 Evolution
6 Benefits
6.1 Resistance to catastrophe
6.2 Food and drink
6.3 Medicines
6.4 Industrial materials
6.5 Intellectual value
6.6 Better crop-varieties
6.7 Other ecological services
6.8 Leisure, cultural and aesthetic value
7 Hindrances
7.1 Funds
7.2 Withheld resources
7.3 Preservation of invertebrate and plant species
8 Numbers of species
9 Threats
9.1 Destruction of habitats
9.2 Exotic species
9.3 Genetic pollution
9.4 Hybridization and genetics
10 Management
11 Judicial status
12 Criticisms
12.1 Food
12.2 Founder effect
12.3 Size bias
13 See also
14 References
15 Further reading
16 External links
16.1 United Nations
16.1.1 Documents
16.1.2 Tools
16.1.3 Scholarly Articles
16.2 National
16.3 Education Institutions
16.4 Resources
16.5 News

Evolution and meaning
Biodiversity is a neologism and portmanteau word, from biology and diversity. The Science Division of The Nature Conservancy used the term "natural diversity" in a 1975 study, "The Preservation of Natural Diversity." The term biological diversity was used even before that by conservation scientists like Robert E. Jenkins and Thomas Lovejoy. The word biodiversity itself may have been coined by W.G. Rosen in 1985 while planning the National Forum on Biological Diversity organized by the National Research Council (NRC) which was to be held in 1986, and first appeared in a publication in 1988 when entomologist E. O. Wilson used it as the title of the proceedings [1] of that forum.[2] The word biodiversity was deemed more effective in terms of communication than biological diversity
Since 1986 the terms and the concept have achieved widespread use among biologists, environmentalists, political leaders, and concerned citizens worldwide. It is generally used to equate to a concern for the natural environment and nature conservation. This use has coincided with the expansion of concern over extinction observed in the last decades of the 20th century.
The term "natural heritage" pre-dates "biodiversity", though it is a less scientific term and more easily comprehended in some ways by the wider audience interested in conservation. "Natural Heritage" was used when Jimmy Carter set up the Georgia Heritage Trust while he was governor of Georgia; Carter's trust dealt with both natural and cultural heritage. It would appear that Carter picked the term up from Lyndon Johnson, who used it in a 1966 Message to Congress. "Natural Heritage" was picked up by the Science Division of The Nature Conservancy when, under Jenkins, it launched in 1974 the network of State Natural Heritage Programs. When this network was extended outside the USA, the term "Conservation Data Center" was suggested by Guillermo Mann and came to be preferred.

Definitions
The most straightforward definition is "variation of life at all levels of biological organization".[3] A second definition holds that biodiversity is a measure of the relative diversity among organisms present in different ecosystems. "Diversity" in this definition includes diversity within a species and among species, and comparative diversity among ecosystems.
A third definition that is often used by ecologists is the "totality of genes, species, and ecosystems of a region". An advantage of this definition is that it seems to describe most circumstances and present a unified view of the traditional three levels at which biodiversity has been identified:
genetic diversity - diversity of genes within a species. There is a genetic variability among the populations and the individuals of the same species. (See also population genetics.)
species diversity - diversity among species in an ecosystem. "Biodiversity hotspots" are excellent examples of species diversity.
ecosystem diversity - diversity at a higher level of organization, the ecosystem. Diversity of habitat in a given unit area. To do with the variety of ecosystems on Earth.
The 1992 United Nations Earth Summit in Rio de Janeiro defined "biodiversity" as "the variability among living organisms from all sources, including, 'inter alia', terrestrial, marine, and other aquatic ecosystems, and the ecological complexes of which they are part: this includes diversity within species, between species and of ecosystems". This is, in fact, the closest thing to a single legally accepted definition of biodiversity, since it is the definition adopted by the United Nations Convention on Biological Diversity.
If the gene is the fundamental unit of natural selection, according to E. O. Wilson, the real biodiversity is genetic diversity. For geneticists, biodiversity is the diversity of genes and organisms. They study processes such as mutations, gene exchanges, and genome dynamics that occur at the DNA level and generate evolution.
For ecologists, biodiversity is also the diversity of durable interactions among species. It not only applies to species, but also to their immediate environment (biotope) and their larger ecoregion. In each ecosystem, living organisms are part of a whole, interacting with not only other organisms, but also with the air, water, and soil that surround them..

Measurement

It has been suggested that some content from this article be split into a separate article entitled Measurement of biodiversity. (Discuss)
Biodiversity is a broad concept, so a variety of objective measures have been created in order to empirically measure biodiversity. Each measure of biodiversity relates to a particular use of the data.
For practical conservationists, this measure should quantify a value that is broadly shared among locally affected people. For others, a more economically defensible definition should allow the ensuring of continued possibilities for both adaptation and future use by people, assuring environmental sustainability.
As a consequence, biologists argue that this measure is likely to be associated with the variety of genes. Since it cannot always be said which genes are more likely to prove beneficial, the best choice for conservation is to assure the persistence of as many genes as possible. For ecologists, this latter approach is sometimes considered too restrictive, as it prohibits ecological succession.
Biodiversity is usually plotted as taxonomic richness of a geographic area, with some reference to a temporal scale. Whittaker [4] described three common metrics used to measure species-level biodiversity, encompassing attention to species richness or species evenness:
Species richness - the least sophisticated of the indices available.
Simpson index
Shannon index
There are three other indices which are used by ecologists:
Alpha diversity refers to diversity within a particular area, community or ecosystem, and is measured by counting the number of taxa within the ecosystem (usually species)
Beta diversity is species diversity between ecosystems; this involves comparing the number of taxa that are unique to each of the ecosystems.
Gamma diversity is a measure of the overall diversity for different ecosystems within a region.

Distribution
Biodiversity is not distributed evenly on Earth. It is consistently richer in the tropics and in other localized regions such as the California Floristic Province. As one approaches polar regions one generally finds fewer species. Flora and fauna diversity depends on climate, altitude, soils and the presence of other species. In the year 2006 large numbers of the Earth's species are formally classified as rare or endangered or threatened species; moreover, most scientists estimate that there are millions more species actually endangered which have not yet been formally recognized. About 40 percent of the 40,177 species assessed using the IUCN Red List criteria, are now listed as threatened species with extinction - a total of 16,119 species.[5]
A biodiversity hotspot is a region with a high level of endemic species. These biodiversity hotspots were first identified by Dr. Norman Myers in two articles in the scientific journal The Environmentalist.[6][7] Dense human habitation tends to occur near hotspots. Most hotspots are located in the tropics and most of them are forests.
Brazil's Atlantic Forest is considered a hotspot of biodiversity and contains roughly 20,000 plant species, 1350 vertebrates, and millions of insects, about half of which occur nowhere else in the world. The island of Madagascar including the unique Madagascar dry deciduous forests and lowland rainforests possess a very high ratio of species endemism and biodiversity, since the island separated from mainland Africa 65 million years ago, most of the species and ecosystems have evolved independently producing unique species different from those in other parts of Africa.
Many regions of high biodiversity (as well as high endemism) arise from very specialized habitats which require unusual adaptation mechanisms. For example the peat bogs of Northern Europe and the alvar regions such as the Stora Alvaret on Oland, Sweden host a large diversity of plants and animals, many of which are not found elsewhere.

Evolution
Apparent marine fossil diversity during the Phanerozoic
Biodiversity found on Earth today is the result of 4 billion years of evolution. The origin of life has not been definitely established by science, though evidence suggests that life may already have been well-established a few 100 million years after the formation of the Earth. Until approximately 600 million years ago, all life consisted of bacteria and similar single-celled organisms.
The history of biodiversity during the Phanerozoic (the last 540 million years), starts with rapid growth during the Cambrian explosion—a period during which nearly every phylum of multicellular organisms first appeared. Over the next 400 million years or so, global diversity showed little overall trend, but was marked by periodic, massive losses of diversity classified as mass extinction events.
The apparent biodiversity shown in the fossil record suggests that the last few million years include the period of greatest biodiversity in the Earth's history. However, not all scientists support this view, since there is considerable uncertainty as to how strongly the fossil record is biased by the greater availability and preservation of recent geologic sections. Some (e.g. Alroy et al. 2001) argue that corrected for sampling artifacts, modern biodiversity is not much different from biodiversity 300 million years ago.[8] Estimates of the present global macroscopic species diversity vary from 2 million to 100 million species, with a best estimate of somewhere near 13-14 million, the vast majority of them arthropods.[9]
Most biologists agree however that the period since the emergence of humans is part of a new mass extinction, the Holocene extinction event, caused primarily by the impact humans are having on the environment. It has been argued that the present rate of extinction is sufficient to eliminate most species on the planet Earth within 100 years.[10]
New species are regularly discovered (on average between 5-10,000 new species each year, most of them insects) and many, though discovered, are not yet classified (estimates are that nearly 90% of all arthropods are not yet classified).[9] Most of the terrestrial diversity is found in tropical forests.

Benefits
There are a multitude of benefits of biodiversity in the sense of one diverse group aiding another such as:
[edit] Resistance to catastrophe
Monoculture, the lack of biodiversity, was a contributing factor to several agricultural disasters in history, including the Irish Potato Famine, the European wine industry collapse in the late 1800s, and the US Southern Corn Leaf Blight epidemic of 1970.[11] See also: Agricultural biodiversity
Higher biodiversity also controls the spread of certain diseases as viruses will need adapt to infect different species.
[edit] Food and drink
Biodiversity provides food for humans. Although about 80 percent of our food supply comes from just 20 kinds of plants, humans use at least 40,000 species of plants and animals a day. Many people around the world depend on these species for their food, shelter, and clothing. There is untapped potential for increasing the range of food products suitable for human consumption, provided that the high present extinction rate can be stopped.[10]
[edit] Medicines
A significant proportion of drugs are derived, directly or indirectly, from biological sources; in most cases these medicines can not presently be synthesized in a laboratory setting. About 40% of the pharmaceuticals used in the US are manufactured using natural compounds found in plants, animals, and microorganisms. Moreover, only a small proportion of the total diversity of plants has been thoroughly investigated for potential sources of new drugs. Many drugs are also derived from microorganisms.
[edit] Industrial materials
A wide range of industrial materials are derived directly from biological resources. These include building materials, fibers, dyes, resins, gums, adhesives, rubber and oil. There is enormous potential for further research into sustainably utilizing materials from a wider diversity of organisms.
[edit] Intellectual value
Through the field of bionics, considerable technological advancement has occurred which would not have without a rich biodiversity. (See also: Bionics)
[edit] Better crop-varieties
For some foodcrops and other economic crops, wild varieties of the domesticated species can be reintroduced to form a better variety than the previous (domesticated) species. The economic impact is gigantic, for even crops as common as the potato (which was bred through only one variety, brought back from the Inca), a lot more can come from these species. Wild varieties of the potato will all suffer enormously through the effects of climate change. A report by the Consultative Group on International Agricultural Research (CGIAR) describes the huge economic loss. Rice, which has been improved for thousands of years by humans, can through the same process regain some of its nutritional value that has been lost since (a project is already being carried out to do just this).
Crop diversity is also necessary to help the system recover when the dominant crop type is attacked by a disease:
The Irish potato blight of 1846, which (was a major factor in the deaths) of a million people and migration of another million, was the result of planting only two potato varieties, both of which were vulnerable.
When the rice grassy stunt virus struck rice fields from Indonesia to India in the 1970s, 6273 varieties were tested. Only one was luckily found to be resistant, a relatively feeble Indian variety, known to science only since 1966, with the desired trait. It was hybridised with other varieties and now widely grown.
In 1970, coffee rust attacked coffee plantations in Sri Lanka, Brazil, and Central America. A resistant variety was found in Ethiopia, coffee's presumed homeland, which mitigated the rust epidemic.[12]
[edit] Other ecological services
Biodiversity provides many ecosystem services that are often not readily visible. It plays a part in regulating the chemistry of our atmosphere and water supply. Biodiversity is directly involved in recycling nutrients and providing fertile soils. Experiments with controlled environments have shown that humans cannot easily build ecosystems to support human needs; for example insect pollination cannot be mimicked by human-made construction, and that activity alone represents tens of billions of dollars in ecosystem services per annum to humankind.
[edit] Leisure, cultural and aesthetic value
Many people derive value from biodiversity through leisure activities such as hiking in the countryside, birdwatching or natural history study.
Biodiversity has inspired musicians, painters, sculptors, writers and other artists. Many cultural groups view themselves as an integral part of the natural world and show respect for other living organisms.
Popular activities such as gardening, caring for aquariums and collecting butterflies are all strongly dependent on biodiversity. The number of species involved in such pursuits is in the tens of thousands, though the great majority do not enter mainstream commercialism.
The relationships between the original natural areas of these often 'exotic' animals and plants and commercial collectors, suppliers, breeders, propagators and those who promote their understanding and enjoyment are complex and poorly understood. It seems clear, however, that the general public responds well to exposure to rare and unusual organisms-- they recognize their inherent value at some level, even if they would not want the responsibility of caring for them. A family outing to the botanical garden or zoo is as much an aesthetic or cultural experience as it is an educational one.
Philosophically it could be argued that biodiversity has intrinsic aesthetic and/or spiritual value to mankind in and of itself. This idea can be used as a counterweight to the rather notion that tropical forests and other ecological realms are only worthy of conservation because they may contain medicines or useful products.

Hindrances
[edit] Funds
Humans have generally expanded and developed their territory throughout history. An active approach is the only way to halt the expansion but this often requires funds or wise stewardship. Currently the United States Environmental Protection Agency has an annual budget of $7.3 billion (2007).[13]
[edit] Withheld resources
Many times natural resources cannot be exploited due to environmental protection acts. Fine woods from South America and oil from Alaska are prime examples, where even minor human activities are deemed too disruptive to the overall health and biodiversity of an area to be allowed.
[edit] Preservation of invertebrate and plant species
Biodiversity is most well known to the public as a loss of animals with a backbone, when in fact there exist 20 times that number of insects and five times as many flowering plants. While many of these species may be highly valuable to the human race for the above reasons, the vast majority are often completely unknown to anyone but specialists. In fact it is often estimated that less than half and perhaps less than two-thirds of earth organisms have even been identified.

Numbers of species
Insects make up the vast majority of animal species.
As a soft guide, however, the numbers of identified modern species as of 2004 can be broken down as follows:[14]
287,655 plants, including:
15,000 mosses,
13,025 ferns,
980 gymnosperms,
199,350 dicotyledons,
59,300 monocotyledons;
74,000-120,000 fungi;[15]
10,000 lichens;
1,250,000 animals, including:
1,190,200 invertebrates:
950,000 insects,
70,000 mollusks,
40,000 crustaceans,
130,200 others;
58,808 vertebrates:
29,300 fish,
5,743 amphibians,
8,240 reptiles,
10,234 birds, (9799 extant as of 2006)
5,416 mammals.
However the total number of species for some phyla may be much higher:
10-30 million insects;[16]
5-10 million bacteria;[17]
1.5 million fungi;[15]
~1 million mites [18]

Threats
During the last century, erosion of biodiversity has been increasingly observed. Some studies show that about one eighth known plant species is threatened with extinction[specify]. Some estimates put the loss at up to 140,000 species per year (based on Species-area theory) and subject to discussion.[19] This figure indicates unsustainable ecological practices, because only a small number of species come into being each year. Almost all scientists acknowledge[citation needed] that the rate of species loss is greater now than at any time in human history, with extinctions occurring at rates hundreds of times higher than background extinction rates.
The factors that threaten biodiversity have been variously categorized. Jared Diamond describes an "Evil Quartet" of habitat destruction, overkill, introduced species, and secondary extensions. Edward Wilson prefers the acronym HIPPO, standing for Habitat destruction, Invasive species, Pollution, Population, and Overharvesting.[20][21]
[edit] Destruction of habitats
Most of the species extinctions from 1000 AD to 2000 AD are due to human activities, in particular destruction of plant and animal habitats. Raised rates of extinction are being driven by human consumption of organic resources, especially related to tropical forest destruction.[22] While most of the species that are becoming extinct are not food species, their biomass is converted into human food when their habitat is transformed into pasture, cropland, and orchards. It is estimated that more than 40% of the Earth's biomass[citation needed] is tied up in only the few species that represent humans, livestock and crops. Because an ecosystem decreases in stability as its species are made extinct, these studies warn that the global ecosystem is destined for collapse if it is further reduced in complexity. Factors contributing to loss of biodiversity are: overpopulation, deforestation, pollution (air pollution, water pollution, soil contamination) and global warming or climate change, driven by human activity. These factors, while all stemming from overpopulation, produce a cumulative impact upon biodiversity.
Some characterize loss of biodiversity not as ecosystem degradation but by conversion to trivial standardized ecosystems (e.g., monoculture following deforestation). In some countries lack of property rights or access regulation to biotic resources necessarily leads to biodiversity loss (degradation costs having to be supported by the community).
A September 14, 2007 study conducted by the National Science Foundation found that biodiversity and genetic diversity are dependent upon each other--that diversity within a species is necessary to maintain diversity among species, and vice versa. According to the lead researcher in the study, Dr. Richard Lankau, "If any one type is removed from the system, the cycle can break down, and the community becomes dominated by a single species."[23]
[edit] Exotic species
Main article: Introduced species
The rich diversity of unique species across many parts of the world exist only because they are separated by barriers, particularly large rivers, seas, oceans, mountains and deserts from other species of other land masses, particularly the highly fecund, ultra-competitive, generalist "super-species". These are barriers that could never be crossed by natural processes, except for many millions of years in the future through continental drift. However humans have invented ships and airplanes, and now have the power to bring into contact species that never have met in their evolutionary history, and on a time scale of days, unlike the centuries that historically have accompanied major animal migrations.
The widespread introduction of exotic species by humans is a potent threat to biodiversity. When exotic species are introduced to ecosystems and establish self-sustaining populations, the endemic species in that ecosystem, that have not evolved to cope with the exotic species, may not survive. The exotic organisms may be either predators, parasites, or simply aggressive species that deprive indigenous species of nutrients, water and light. These exotic or invasive species often have features, due to their evolutionary background and new environment, that make them highly competitive; able to become well-established and spread quickly, reducing the effective habitat of endemic species.
As a consequence of the above, if humans continue to combine species from different ecoregions, there is the potential that the world's ecosystems will end up dominated by relatively a few, aggressive, cosmopolitan "super-species".
Other 'Decline in amphibian populations'
Main article: Decline in amphibian populations
Declines in amphibian populations have been observed since 1980s. Because of the sensitivity of these organisms, they are regarded by many scientists as a marker for the overall health of an ecosystem. Their decline has led to concern about the general current state of biodiversity. a;soeifj;asldkjf
[edit] Genetic pollution
Main article: Genetic pollution
Purebred naturally evolved region specific wild species can be threatened with extinction in a big way[24] through the process of Genetic Pollution i.e. uncontrolled hybridization, introgression and Genetic swamping which leads to homogenization or replacement of local genotypes as a result of either a numerical and/or fitness advantage of introduced plant or animal.[25] Nonnative species can bring about a form of extinction of native plants and animals by hybridization and introgression either through purposeful introduction by humans or through habitat modification, bringing previously isolated species into contact. These phenomena can be especially detrimental for rare species coming into contact with more abundant ones where the abundant ones can interbreed with them swamping the entire rarer gene pool creating hybrids thus driving the entire original purebred native stock to complete extinction. Attention has to be focused on the extent of this under appreciated problem that is not always apparent from morphological (outward appearance) observations alone. Some degree of gene flow may be a normal, evolutionarily constructive process, and all constellations of genes and genotypes cannot be preserved however, hybridization with or without introgression may, nevertheless, threaten a rare species' existence.[26][27]
[edit] Hybridization and genetics
See also: food security
In agriculture and animal husbandry, green revolution popularized the use of conventional hybridization to increase yield many folds by creating "high-yielding varieties". Often the handful of breeds of plants and animals hybridized originated in developed countries and were further hybridized with local varieties, in the rest of the developing world, to create high yield strains resistant to local climate and diseases. Local governments and industry since have been pushing hybridization with such zeal that several of the wild and indigenous breeds evolved locally over thousands of years having high resistance to local extremes in climate and immunity to diseases etc. have already become extinct or are in grave danger of becoming so in the near future. Due to complete disuse because of un-profitability and uncontrolled intentional, compounded with unintentional cross-pollination and crossbreeding (genetic pollution) formerly huge gene pools of various wild and indigenous breeds have collapsed causing widespread genetic erosion and genetic pollution resulting in great loss in genetic diversity and biodiversity as a whole.[28]
A genetically modified organism (GMO) is an organism whose genetic material has been altered using the genetic engineering techniques generally known as recombinant DNA technology. Genetically Modified (GM) crops today have become a common source for genetic pollution, not only of wild varieties but also of other domesticated varieties derived from relatively natural hybridization.[29][30][31][32][33]
It is being said that genetic erosion coupled with genetic pollution is destroying that needed unique genetic base thereby creating an unforeseen hidden crisis which will result in a severe threat to our food security for the future when diverse genetic material will cease to exist to be able to further improve or hybridize weakening food crops and livestock against more resistant diseases and climatic changes.[34]
Management
Main article: Conservation biology
The conservation of biological diversity has become a global concern. Although not everybody agrees on extent and significance of current extinction, most consider biodiversity essential. There are basically two main types of conservation options, in-situ conservation and ex-situ conservation. In-situ is usually seen as the ideal conservation strategy. However, its implementation is sometimes infeasible. For example, destruction of rare or endangered species' habitats sometimes requires ex-situ conservation efforts. Furthermore, ex-situ conservation can provide a backup solution to in-situ conservation projects. Some believe both types of conservation are required to ensure proper preservation. An example of an in-situ conservation effort is the setting-up of protection areas. Examples of ex-situ conservation efforts, by contrast, would be planting germplasts in seedbanks, or growing the Wollemi Pine in nurseries. Such efforts allow the preservation of large populations of plants with minimal genetic erosion.
At national levels a Biodiversity Action Plan is sometimes prepared to state the protocols necessary to protect an individual species. Usually this plan also details extant data on the species and its habitat. In the USA such a plan is called a Recovery Plan.
The threat to biological diversity was among the hot topics discussed at the UN World Summit for Sustainable Development, in hope of seeing the foundation of a Global Conservation Trust to help maintain plant collections.
[edit] Judicial status
Biodiversity is beginning to be evaluated and its evolution analysed (through observations, inventories, conservation...) as well as being taken into account in political and judicial decisions: .
The relationship between law and ecosystems is very ancient and has consequences for biodiversity. It is related to property rights, both private and public. It can define protection for threatened ecosystems, but also some rights and duties (for example, fishing rights, hunting rights).
Law regarding species is a more recent issue. It defines species that must be protected because they may be threatened by extinction. The U.S. Endangered Species Act is an example of an attempt to address the "law and species" issue.
Laws regarding gene pools are only about a century old[citation needed]. While the genetic approach is not new (domestication, plant traditional selection methods), progress made in the genetic field in the past 20 years have led to a tightening of laws in this field. With the new technologies of genetic analysis and genetic engineering, people are going through gene patenting, processes patenting, and a totally new concept of genetic resources[citation needed]. A very hot debate today seeks to define whether the resource is the gene, the organism itself, or its DNA.
The 1972 UNESCO convention established that biological resources, such as plants, were the common heritage of mankind. These rules probably inspired the creation of great public banks of genetic resources, located outside the source-countries.
New global agreements (e.g.Convention on Biological Diversity), now give sovereign national rights over biological resources (not property). The idea of static conservation of biodiversity is disappearing and being replaced by the idea of dynamic conservation, through the notion of resource and innovation.
The new agreements commit countries to conserve biodiversity, develop resources for sustainability and share the benefits resulting from their use. Under new rules, it is expected that bioprospecting or collection of natural products has to be allowed by the biodiversity-rich country, in exchange for a share of the benefits.
Sovereignty principles can rely upon what is better known as Access and Benefit Sharing Agreements (ABAs). The Convention on Biodiversity spirit implies a prior informed consent between the source country and the collector, to establish which resource will be used and for what, and to settle on a fair agreement on benefit sharing. Bioprospecting can become a type of biopiracy when those principles are not respected.
Uniform approval for use of biodiversity as a legal standard has not been achieved, however. At least one legal commentator has argued that biodiversity should not be used as a legal standard, arguing that the multiple layers of scientific uncertainty inherent in the concept of biodiversity will cause administrative waste and increase litigation without promoting preservation goals. See Fred Bosselman, A Dozen Biodiversity Puzzles, 12 N.Y.U. Environmental Law Journal 364 (2004)
Criticisms

Some of the biodiversity of a coral reef.
[edit] Food
Many have challenged the notion that there is 'vast untapped potential' for reducing humankind's dependence on a relatively small number of domesticated plant and animal species. Jared Diamond,[35] based on studies of the domestication of plants and animals, argued that the rarity of species suitable for domestication and their occurrence in just a few parts of the world, determined the limited number of locations in which major civilizations could arise. In recent times there have been many studies of minor food sources, but none of these sources have subsequently become major food crops.
[edit] Founder effect
The field of biodiversity research (inevitably) suffers from natural human egocentric "myopic" cognitive biases. It has often been criticized for being overly defined by the personal interests of the founders (i.e. terrestrial mammals) giving a narrow focus, rather than extending to other areas where it could be useful. This is termed the founder effect by Norse and Irish, (1996).[36] (This was a play on words: the founder effect in ecology typically refers to the genetic outcome when a small population establishes an isolated breeding group). France and Rigg reviewed the biodiversity literature in 1998 and found that there was a significant lack of papers studying marine ecosystems,[37] leading them to dub marine biodiversity research the sleeping hydra. More work has been carried out for accessible, diverse coastal systems such as coral reefs than for inaccessible, species-poor deep sea areas.
It has been easier to mobilise public opinion and national legislation for the terrestrial realm, which has higher visibility and falls within countries' territorial boundaries. Marine conservation involves having to pioneer new and international mechanisms of protection as well as solving methodological problems in marine biology relating to marine ecosystem classification and data-gathering on some of the earth's most difficult species to access and monitor.
[edit] Size bias
Biodiversity researcher Sean Nee points out that the vast majority of Earth's biodiversity is microbial, and that contemporary biodiversity physics is "firmly fixated on the visible world" (Nee uses "visible" as a synonym for macroscopic).[38] For example, microbial life is very much more metabolically and environmentally diverse than multicellular life (see extremophile). Nee has stated: "On the tree of life, based on analyses of small-subunit ribosomal RNA, visible life consists of barely noticeable twigs.
The size bias is not restricted to consideration of microbes. Entomologist Nigel Stork states that "to a first approximation, all multicellular species on Earth are insects".[39]
A reply to this, however, is that biodiversity conservation has never focused exclusively on visible (in this sense) species. From the very beginning, the classification and conservation of natural communities or ecosystem types has been a central part of the effort. The thought behind this has been that since invisible (in this sense) diversity is, due to lack of taxonomy, impossible to treat in the same manner as visible diversity, the best that can be done is to preserve a diversity of ecosystem types, thereby preserving as well as possible the diversity of invisible organisms.
See also

Adaptation
Amazonian forest
Applied ecology
Ecological Economics
Extinction
Biocomplexity
biogeography
Bioinformatics
Canadian Biodiversity Information Network
Conservation Commons
Conservation ethic
Convention on Biological Diversity
Ecology
Forest farming
Ewens sampling formula
Gene pool
Genetic Pollution
Genetic Erosion
Global 200
Green Revolution
Habitat fragmentation
IUCN
Intermediate Disturbance Hypothesis
International Institute of Tropical Agriculture
International Treaty on Plant Genetic Resources for Food and Agriculture
Like-Minded Megadiverse Countries (LMMC), a group of 17 megadiverse countries, formed in February 2002
Megadiverse countries
Millennium Ecosystem Assessment
Millennium Seed Bank Project
Monoculture
Mutation
National Biodiversity Network
Ongoing mass extinction of species
Seed bank
Unified neutral theory of biodiversity
United States environmental law
Wildlife preserve
World Conservation Monitoring Centre
World Conservation Union
World Network of Biosphere Reserves

References

This article uses bare URLs for citations, which are subject to link rot.Please help improve this article by changing bare URLs into proper citations with titles, dates, and authors, so that the article remains verifiable in the future.
^ Edward O.Wilson, editor, Frances M.Peter, associate editor, Biodiversity, National Academy Press, March 1988 ISBN 0-309-03783-2 ; ISBN 0-309-03739-5 (pbk.), online edition
^ Global Biodiversity Assessment. UNEP, 1995, Annex 6, Glossary. ISBN 0-521-56481-6, used as source by "Biodiversity", Glossary of terms related to the CBD, Belgian Clearing-House Mechanism, retrieved 2006-04-26.
^ Kevin J. Gaston & John I. Spicer. 2004. "Biodiversity: an introduction", Blackwell Publishing. 2nd Ed., ISBN 1-4051-1857-1(pbk.)
^ Whittaker, R.H., Evolution and measurement of species diversity, Taxon, 21, 213-251 (1972)
^ Endangered Species List Expands to 16,000. Retrieved on 2007-11-13.
^ Myers N. (1988), "Threatened biotas: 'hot spots' in tropical forests", Environmentalist, 8, 187-208.
^ Myers N. (1990), "The biodiversity challenge: expanded hot-spots analysis", Environmentalist, 10, 243-256.
^ J. Alroy, C.R. et al.2001. Effect of sampling standardization on estimates of Phanerozonic marine diversification. Proceedings of the National Academy of Science, USA 98: 6261-6266
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^ a b Edward O. Wilson (2002). The Future of Life. New York: Alfred A. Knopf.
^ Southern Corn Leaf Blight. Retrieved on 2007-11-13.
^ GM Wahl, BR de Saint Vincent and ML DeRose, Effect of chromosomal position on amplificationm of transfected genes in animal cells, Nature 307:516-520
^ [2]
^ [3]
^ a b David L. Hawksworth, "The magnitude of fungal diversity: the 1•5 million species estimate revisited" Mycological Research (2001), 105: 1422-1432 Cambridge University Press [4]
^ [5]
^ Proceedings of the National Academy of Sciences, Census of Marine Life (CoML) [6]
^ [7]
^ S.L. Pimm, G.J. Russell, J.L. Gittleman and T.M. Brooks, The Future of Biodiversity, Science 269: 347-350 (1995)
^ Jim Chen (2003). "Across the Apocalypse on Horseback: Imperfect Legal Responses to Biodiversity Loss", The Jurisdynamics of Environmental Protection: Change and the Pragmatic. Environmental Law Institute, 197. ISBN 1585760714.
^ (2005) "Hippo dilemma", Windows on the Wild: Science and Sustainabiliy. New Africa Books. ISBN 1869283805.
^ Paul Ehrlich and Anne Ehrlich, Extinction, Random House, New York (1981) ISBN 0-394-51312-6
^ Study: Loss Of Genetic Diversity Threatens Species Diversity
^ Hybridization and Introgression; Extinctions; from "The evolutionary impact of invasive species; by H. A. Mooney and E. E. Cleland" Proc Natl Acad Sci U S A. 2001 May 8; 98(10): 5446–5451. doi:10.1073/pnas.091093398. Proc Natl Acad Sci U S A, v.98(10); May 8, 2001, The National Academy of Sciences. PMID 33232
^ Glossary: definitions from the following publication: Aubry, C., R. Shoal and V. Erickson. 2005. Grass cultivars: their origins, development, and use on national forests and grasslands in the Pacific Northwest. USDA Forest Service. 44 pages, plus appendices.; Native Seed Network (NSN), Institute for Applied Ecology, 563 SW Jefferson Ave, Corvallis, OR 97333, USA
^ EXTINCTION BY HYBRIDIZATION AND INTROGRESSION; by Judith M. Rhymer , Department of Wildlife Ecology, University of Maine, Orono, Maine 04469, USA; and Daniel Simberloff, Department of Biological Science, Florida State University, Tallahassee, Florida 32306, USA; Annual Review of Ecology and Systematics, November 1996, Vol. 27, Pages 83-109 (doi: 10.1146/annurev.ecolsys.27.1.83), [8]
^ Genetic Pollution from Farm Forestry using eucalypt species and hybrids; A report for the RIRDC/L&WA/FWPRDC; Joint Venture Agroforestry Program; by Brad M. Potts, Robert C. Barbour, Andrew B. Hingston; September 2001; RIRDC Publication No 01/114; RIRDC Project No CPF - 3A; ISBN 0 642 58336 6; ISSN 1440-6845; Australian Government, Rural Industrial Research and Development Corporation
^ http://www.farmedia.org/bulletins/bulletin28.html, [9]
^ THE YEAR IN IDEAS: A TO Z.; Genetic Pollution; By MICHAEL POLLAN, The New York Times, December 9, 2001
^ http://www.nature.com/nbt/journal/v22/n1/full/nbt0104-29.html
^ “Genetic pollution: Uncontrolled spread of genetic information (frequently referring to transgenes) into the genomes of organisms in which such genes are not present in nature.” Zaid, A. et al. 1999. Glossary of biotechnology and genetic engineering. FAO Research and Technology Paper No. 7. ISBN 92-5-104369-8
^ “Genetic pollution: Uncontrolled escape of genetic information (frequently referring to products of genetic engineering) into the genomes of organisms in the environment where those genes never existed before.” Searchable Biotechnology Dictionary. University of Minnesota. , [10]
^ “Genetic pollution: Living organisms can also be defined as pollutants, when a non-indigenous species (plant or animal) enters a habitat and modifies the existing equilibrium among the organisms of the affected ecosystem (sea, lake, river). Non-indigenous, including transgenic species (GMOs), may bring about a particular version of pollution in the vegetable kingdom: so-called genetic pollution. This term refers to the uncontrolled diffusion of genes (or transgenes) into genomes of plants of the same type or even unrelated species where such genes are not present in nature. For example, a grass modified to resist herbicides could pollinate conventional grass many miles away, creating weeds immune to the most widely used weed-killer, with obvious consequences for crops. Genetic pollution is at the basis of the debate on the use of GMOs in agriculture.” The many facets of pollution; Bologna University web site for Science Communication. The Webweavers: Last modified Tue, 20 Jul 2005
^ http://www.farmedia.org/bulletins/bulletin28.html, [11]
^ Diamond, J.(1998), Guns, Germs and Steel. Vintage. ISBN 0 09 930278 0 (pbk.)
^ Irish, K.E. and Norse, E.A. (1996) Scant emphasis on marine biodiversity Conserv. Biol. 10 680
^ France, R., and Rigg, C. (1998) Examination of the 'founder effect' in biodiversity research: patterns and imbalances in the published literature Diversity and Distributions 4 77-86
^ Nee S. (2004), "More than meets the eye",Nature, 429, 804-805.
^ N. E. Stork 2007. Biodiversity: world of Insects. Nature 448, 657-658 (9 August 2007)
Further reading
Leveque, C. & J. Mounolou (2003) Biodiversity. New York: John Wiley. ISBN 0470849576
Margulis, L., Dolan, Delisle, K., Lyons, C. Diversity of Life: The Illustrated Guide to the Five Kingdoms. Sudbury: Jones & Bartlett Publishers. ISBN 0763708623
Alexander V. Markov, and Andrey V. Korotayev (2007) "Phanerozoic marine biodiversity follows a hyperbolic trend" Palaeoworld 16(4): pp. 311-318.
Novacek, M. J. (ed.) (2001) The Biodiversity Crisis: Losing What Counts. New York: American Museum of Natural History Books. ISBN 1565845706
[edit] External links

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[edit] United Nations
[edit] Documents
Convention on Biological Diversity Text of the Convention
Global Biodiversity Outlook 2 a publication of the Secretariat of the Convention on Biological Diversity that reviews the trends in biodiversity loss, and the responses under the Convention.
Biodiversity Synthesis Report (PDF) by the Millennium Ecosystem Assessment (MA, 2005)
[edit] Tools
World Map of Biodiversity an interactive map from the United Nations Environment Programme World Conservation Monitoring Centre
GLOBIO, an ongoing programme to map the past, current and future impacts of human activities on biodiversity
[edit] Scholarly Articles
The significance of Vavilov’s scientific expeditions and ideas for development and use of legume genetic resources
Diversity of lupin (Lupinus L.) based on biochemical composition
Climate Change Threatens Wild Relatives of Key Crops
[edit] National
Canadian Biodiversity Information Network
National Biodiversity Network
[edit] Education Institutions
Where can I study Biodiversity and Conservation?
Stanford Encyclopedia of Philosophy: Biodiversity
[edit] Resources
Biodiversity Heritage Library http://www.biodiversitylibrary.org/ - Open access digital library of taxonomic literature
DMOZ http://dmoz.org/Science/Environment/Biodiversity/ - Open Directory Project
ERIC Digests http://www.ericdigests.org/2000-2/biodiversity.htm - Teaching about Biodiversity
National Biodiversity Network http://www.searchnbn.net/ - NBN Gateway
[edit] News
Gone: By the End of the Century Half of All Plant and Animal Species Will be Extinct; Who Will Survive? by Julia Whitty from the May/June 2007 issue of Mother Jones magazine
Whole Earth 'Lectronic Link http://www.well.com/user/davidu/extinction.html - Compiled news about current rate of biodiversity loss and species extinction
Inter Press Service [12] - One Planet - 1.4 Million Species : : Reports and analysis about biodiversity

زندگی خانواده لک لک ها

2008-09-06T00:40:00.000-07:00

زندگي خانوادگي لك لك ها : ۵/۶/۸۶
لک لک ها نمونه و سمبل مهر و محبت و عشق و صفا شناخته شده اند و حتی می توان ادعا نمود که در انی مورد از انسانها نیز جلوتر هستند و اعمالیکه انجام می دهند ب هوش و نبوغ آنها دلالت دارد که به نمونه ای چند از انها اشاره می کنم:
مراسم ازدواج لک لک ها بسیار جالب و دیدنی می باشد .دو لک لک جوان آماده ازدواج در وسط و در اطراف آنها بالغ بر 50 لک لک اجتماع کرده و سروصدا راه می اندازند پس از ازدواج دو لک لک نر و ماده معمولا خانواده عروس یک آشیانه به زوجین اهدا می نمایند که در حکم جهیزیه می باشد .لک لک ها پس از ازدواج تا آخر عمر از هم جدا نمی شوند مگر اینکه بدلیلی بین آنها جدایی و فاصله ایجاد شود.هنگام تاریکی و اوایل شب معمولا لک لک ماده مقابل لانه آمده و با بی صبری در انتظار شوهر به سر می برد پس پس از حضور لک لک نر در نزدیک لانه صداهایی را ایجاد می نماید که لک لک ماده را از حضور خود آگاه می سازد در مقابل لک لک ماده نیز نوک خود را به نوک جفت خویش نزدیک کرده و بدین ترتیب مدتی را به عشق بازی می گذرانند.
غیرت لک لک:
لک لک ها نیز مانند کلاغ ها به شدت ناموس پرستند و تعدد زوجات میان آنها وجود ندارد.تعصب خانوادگی در میان آنها بسیار شدید است. در صورتی که دادگاه لک لک ها رای به اعدام متهمی صادر نماید؛ متهم قبل از اقدام سایرین خودش این کار را انجام می دهد.

ارزشهای حیات وحش (wild life values):

2008-09-06T00:08:00.000-07:00

انجمن دوستداران حیات وحش ایران
وبلاگ رسمی انجمن دوستداران حیات وحش ایزان (همدان)
ارزشهاي حيات وحش (Wild Life Values):
1- ارزش اقتصادي حيات وحش : برابر بهره ي سپرده اي است در بانك كه از آن سود برده مي شود. مثل فروش پروانه ي شكار، اكوتوريست(توريست همراه طبيعت)، فروش تروفه، توليد به منظور استفاده از گوشت و ...مثلا درآمد دو كشور كنيا و تانزانيا فقط از حيات وحش مي باشد. در تانزانيا پارك ملي سرنگتي وجود دارد كه داراي نقش مهمي در تامين درآمد اين كشور دارد. به طوري كه يكي از اقتصاد دانان حيات وحش برآورد كرده كه يك ماده شير طي هفت سال از عمر خود در كشور كنيا 512 هزار دلار درآمد كسب مي كند، در حالي كه اگر اين شير به خاطر استفاده از پوستش كشته شود، فقط 10 هزار دلار ارزش دارد.2- ارزش تفرجي، تفريحي و زيبا شناختي : گونه هاي شكاري وحشي تامين كننده ي تفريحات سالم براي شكارچيان و صيادان هستند.هر سال 50% از مردم آمريكا و 84% از مردم كانادا اوقات فراغت خود را صرف تماشاي پرندگان و عكس برداري از آنها مي كنند.
3- ارزش بيولوژيك (زيستي ) : منظور نقش و اهميت حيات وحش در اكوسيستم ها است.در واقع حيات وحش ارزش و كاركرد مهمي در پايداري اكوسيستم ها و چرخه هاي مواد و انرژي دارند. مثل گراز(Sus scrofa) كه در انتشار دانه ها در طبيعت و زير و رو كردن خاك نقش مهمي دارد. از ديگر مثال هاي اين ارزش ميتوان به موارد زير اشاره كرد :تنظيم جمعيت ها، كنترل موجودات بيماري زا، از بين بردن لاشه ي حيوانات اهلي و وحشي و....
4- ارزش علمي و پژوهشي : از بعضي از انواع حيات وحش در آزمايشگاه ها به عنوان نمونه استفاده مي شود. به عنوان مثال مي توان از استفاده از پرندگان به عنوان گونه هاي انديكاتور(شاخص) نام برد.
5- ارزش اجتماعي : پيامد ارزش اقتصادي حيات وحش است. اين ارزش در نتيجه ي كسب درآمد از حيات وحش است كه باعث بالا رفتن آگاهي در مورد گونه ها مي شود.
6- ارزشهاي منفي حيات وحش : مثل هزينه هايي كه صرف كنترل، پيشگيري و ترميم خرابي هاي حاصل از حيات وحش ميشود.نمونه هاي بارز گونه هايي كه آفت مزارع و دامها هستند عبارتند از : گراز(Sus scrofa)، گرگ(Canis lupus)، تاپير(Tapire)، تشي(Hystrix indica) و ...
+ نوشته شده توسط فرزاد شاهرخی در چهارشنبه 17 اسفند1384 ساعت 7:35 PM
GetBC(10);

6 نظر
حيات وحش(Wild Life)
تعريف عام : مجموعه بخش زنده و رام نشده ي سياره ي زمين شامل گياهان و جانوران وحشي.
تعريف خاص : كليه ي مهره داراني كه در محيط طبيعي خود يا شبيه آن زندگي مي كنند.
+ نوشته شده توسط فرزاد شاهرخی در چهارشنبه 17 اسفند1384 ساعت 7:10 PM
GetBC(9);

3 نظر
ايران يكي از متنوع ترين مناطق از نظر پستانداران است كه داراي 160 گونه در قالب 9 راسته از پستانداران مي باشد.پستانداران كشور ايران متأثر از سه منطقه مي باشند که عبارتند از :
Palearctic Region-1 (اروپايي): حد شرقي پراكنش آنها در ايران است. مثل مرال(Cervus elaphus)، شوكا(Capreolus capreolus) و سنجابك(Myoxus glis).
Oriental Region-2(هندي): حد شمال غربي پراكنش آنها در ايران است. مثل خرس سياه(Selenarctus thibetanus)، سنجاب بلوچي(Funambulus pennantii)، خدنگ(Herpestes edwardsii) و جرد هندي(Meriones hurrianae).
Ethiopic Region-3(آفريقايي): خاستگاه آنها آفريقاست و ايران حد شمال شرقي پراكندگي آنهاست. مثل رودك عسل خوار(Mellivora capensis) و خفاش میوه خوار (Rousettus egyptiacus).
4- پستانداران ويژه ي ايران : گونه هايي هستند كه در ايران تكامل يافته اند. مثل گور ايراني(Equus hemionus)، گوزن زرد(Dama mesopotamica)، پازن(Capra hircus) و سنجاب ايراني(Sciurus anomalus).